1. Field of the Invention
The invention relates to an assembly method and assembly equipment for a power transmission chain of a chain-type continuously variable transmission adopted in, for example, a vehicle.
2. Description of the Related Art
As a power transmission chain used in, for example, a chain-type continuously variable transmission of an automobile, a power transmission chain including a plurality of link plates and a plurality of pin members has been conventionally used. Two pin holes are formed in each link plate with a prescribed pitch. The pin members connect the link plates to each other so that the link plates are flexural with respect to each other. The power transmission chain is formed as an endless chain, by stacking the link plates in their thickness direction and longitudinal direction and press-fitting the pin members into the pin holes (refer to, for example, Japanese Patent No. 4664588). In order to assemble a power transmission chain described in Japanese Patent No. 4664588, pin members are inserted into and held in multiple holes that are formed in an annular assembly jig so as to be arranged along the overall length in the circumferential direction of the assembly jig, and, in this state, half of the multiple link plates are sequentially press-fitted onto portions of the pin members, which protrude from the holes. A subassembly assembled in this way is turned upside down, and the pin members are inserted into the multiple holes of the assembly jig again. Then, the other half of the link plates are press-fitted onto the pin members.
In an assembly method for the power transmission chain described in Japanese Patent No. 4664588, the pin members are held in an unstable state where only one end portions thereof are inserted in the holes of the assembly jig. Therefore, when the link plates are press-fitted onto the pin members, the pin members are easily tilted with respect to the link plates. As a result, clearances may be formed between the link plates and the pin members or the assembled power transmission chain may be distorted. If the subassembly is turned upside down while the pin members are tilted, a work of inserting the pin members into the multiple holes of the assembly jig, again is difficult. This makes an assembly work more time consuming and cumbersome.